FIG. 1 shows an illustration of a cellular communication system, or network, with a serving node 101 that serves a User Equipment (UE) 103 located within the serving node's geographical area of service, called a cell 105. Communication is bidirectional between the serving node 101 and the UE 103. The serving node 101 may, depending on the system, be: a Base Station (BS), a Node B, an evolved Node B (eNodeB or eNB), etc. The UE 103 will use a Radio Access Technology to connect and access a cellular communication system via the serving node 101. Today, there are many radio and cellular access technologies and standards such as GSM/GPRS, GSM/EDGE, WCDMA/HSPA, CDMA-based technologies, WiFi, WiMAX, and LTE, to name a few.
Multi-carrier or carrier aggregation may be used to enhance peak-rates within a RAT. For example, it is possible to use multiple 5 MHz carriers in a HSPA-based RAT to enhance the peak-rate within the HSPA network. Similarly, there is a plan for LTE release 10 to facilitate aggregation of multiple LTE carriers, e.g., aggregation of multiple 20 M Hz carriers. In forthcoming evolutions of cellular systems standards like the Third Generation Partnership Project's (3GPP's) the maximum data rate is sure to be higher than in existing systems. Higher data rates typically require larger system radio spectrum bandwidths. For the International Mobile Telecommunications-Advanced (“IMT-Advanced”) system, i.e., the fourth generation mobile communication systems, bandwidths up to 100 MHz are being discussed. A problem being faced is that the radio spectrum is a limited resource that has to be shared by many operators and systems which makes it very complicated to find 100 MHz of free contiguous spectrum that can be allocated.
One method of overcoming the above mentioned problem is aggregating contiguous and non-contiguous spectrum. FIG. 2 shows an aggregation of two 20 MHz bands 201, 203 and one 10 MHz band 205. The 20 MHz band 203 and the 10 MHz band 205 are contiguous, whereas the 20 MHz band 201 is separated from the 20 MHz and 10 MHz bands 203, 205 by some amount of spectrum 207. The benefit of such a solution is that it becomes possible to generate sufficiently large bandwidths e.g., 50 MHz in the example of FIG. 2, for supporting data rates up to (and above) 1 Gb/s, which is a throughput requirement for a fourth generation (“4G” or IMT-Advanced) system. The ability to utilize an aggregation of non-contiguous as well as contiguous bands of the radio frequency spectrum makes it possible for communication system operators to adapt which parts of the radio spectrum will be used based on present circumstances and to geographical position.
For an operator with a certain bandwidth that must deploy two or more RATs, e.g., HSPA and LTE, if the bandwidth offered in the specific or individual RAT technology is limited to part of the given bandwidth, these carrier aggregation approaches within a RAT cannot fully utilize the whole operator bandwidth. To solve this problem, simultaneous use of multiple RATs may be used, i.e., multi-RAT carrier aggregation. Multi-RAT carrier aggregation (CA) is also termed as multi-RAT multi-carrier, inter-RAT CA, inter-RAT multi-carrier etc. For consistency, the term multi-RAT CA is used. A multi-RAT CA scenario may include adjacent carriers and/or non-adjacent cerriers. Non-adjacent carriers may or may not belong to the same frequency band which means that multi-RAT CA may be intra-band i.e., all RATs in same band, or inter-band i.e., at least 2 RATs/carriers in different bands. Non-limiting of other multi-RAT CA scenarios are: 1) LTE and CDMA2000, 2) LTE and GSM, 3) LTE, HSPA, and GSM, etc.
In systems/networks supporting multiple RATs a Multi-Standard Radio (MSR) Base Station (BS) may be used. A MSR BS comprises common Radio Frequency (RF) components (such as power amplifiers, RF filters etc) which can be used to operate more than one RAT or more than one carrier within the same RAT. More specifically the MSR BS is also termed as Multi-Carrier Multi-Standard Radio (MC-MSR) BS due to the fact that it may comprise of single RAT with more than one carrier. Hence single RAT MSR BS is a special case of the MSR BS. Furthermore a special case of MSR BS may also comprise of a BS, which supports single carrier within a RAT i.e. single carrier single RAT MSR BS. Multi-Carrier Multiple RAT (MC-MR) is another term used for the MSR BS. Nonetheless for simplicity and consistency reasons the term MSR BS will be used further on, which refer to any BS which has common radio parts to operate one or more carriers, which in turn may belong to the same or different RATs.
A MSR BS typically supports either Full Duplex Division (FDD) RATs or Time Division Duplex (TDD) RATs i.e. all RATs in one MSR BS are either FDD or TDD. Note that Half Duplex FDD (HD-FDD) is a special case of the FDD. This means HD-FDD (e.g. EDGE/GERAN/GSM) belongs to FDD MSR BS. The HD-FDD may also be supported for certain bands for E-UTRA FDD or for any FDD based technologies. The technology also applies to the MSR supporting any combination of FDD, HD-FDD and TDD RATs.
The FDD Scenarios include a MSR BS supporting one or more of the following RATs: GSM/GERAN/EDGE, UTRA FDD and E-UTRA FDD. The operating frequency bands specified in 3GPP specification are common for the UTRA FDD and E-UTRA FDD technologies. For example both UTRA FDD and E-UTRA FDD can operate in band 1 (2.1 GHz). However all UTRA FDD and E-UTRA FDD bands are not specified for the GSM/GERAN/EDGE operation. Nonetheless some of the GSM/EGDE/GERAN bands are also specified for the UTRA FDD and E-UTRA FDD; examples of such common bands are: UTRA FDD/E-UTRA FDD bands 3 (1800 MHz) and 8 (900 MHz). For simplicity we will use the term GSM, which covers also GERAN, EDGE and other possible GSM evolution.
The FDD MSR scenarios are classified into the following two frequency band categories: MSR frequency Band Category #1 (BC1): Bands supporting FDD MSR for UTRA FDD and E-UTRA FDD operation e.g. bands 1, 10, 13 etc. MSR frequency Band Category #2 (BC2): Bands supporting FDD MSR for GSM, UTRA FDD and E-UTRA FDD operation e.g. bands 2, 3, 5, 8 etc.
In the case of MSR BC#2, in accordance with the operator deployment scenario, the MSR BS includes the subset of the RATs can be developed. For example a specific MSR BS based on BC#2 may support GSM and UTRA FDD in band 2 in case operator uses only these two RATs.
In future the FDD MSR BS may include other introduced FDD technologies. Examples of these scenarios may comprise of any combination of the following FDD/HD-FDD RATs: S-UTRA FDD and 3GPP2 CDMA technologies (e.g. CDMA2000 1×RTT and HRPD); E-UTRA FDD, UTRA FDD and 3GPP2 CDMA technologies (e.g. CDMA2000 1×RTT and HRPD); and, E-UTRA FDD, UTRA FDD, GSM and 3GPP2 CDMA technologies (e.g. CDMA2000 and HRPD). The technology may also apply to MSR BS comprising of other technologies e.g. WiMax, WLAN and their combination with 3GPP and/or 3GPP2 technologies etc.
The TDD scenarios include a MSR BS supporting one or more of the following RATs: UTRA TDD and E-UTRA TDD. The operating frequency bands specified in 3GPP specification are generally common for the UTRA TDD and E-UTRA TDD technologies. For example both UTRA TDD and E-UTRA TDD can operate in band 38 (2.6 GHz). Hence the TDD MSR scenarios are classified into the following frequency band category: MSR frequency Band Category #3 (BC3): Bands supporting TDD MSR for UTRA FTDD and E-UTRA TDD operation e.g. bands 33, 38, 40 etc.
In view of its common radio circuitry, the MSR BS is required to meet the generic radio requirements, which apply for all RATs and for BS configured for both multi-RAT and single-RAT operation. Non-limiting example of generic radio requirements are unwanted emissions, spurious emissions, out-of-band blocking etc. In addition, there also may be requirements that apply only to certain MSR BS categories/type. For example some of the requirements may be specific to the single RAT GERAN MSR BS. Similarly, modulation quality requirements (e.g. Error Vector Magnitude (EVM)) specific to each RAT needs to be fulfilled by the corresponding RAT.
The MSR BS may have same classes as defined for a non-MSR BS i.e. wide area MSR BS, medium range MSR BS, local area MSR BS and home MSR BS. Different maximum output power levels are used for different BS classes. The wide area MSR BS, medium range MSR BS, local area MSR BS and home MSR BS are typically deployed to serve macro cells, micro cells, pico cells and home/office environments respectively. The MSR BS may also be general purpose BS, which is typically used to serve wide range of environment or hybrid environment. The technology described herein may apply to all types of MSR BS classes.
The MSR BS may also be classified according to whether the carriers in a MSR BS using the common radio parts are contiguous or non-contiguous within the MSR BS bandwidth. Both of the classifications may support different combination of RATs as explained in previous sections.
FIG. 3 shows an example of distribution of multiple carriers/RATs in an example contiguous MSR BS. The symbols shown are defined for example in 3GPP TS37.104. For contiguous MSR, the carriers/RATs are contiguous in the frequency domain.
FIG. 4 shows an example of distribution of carriers and RATs in a non-contiguous MSR (NC-MSR) BS. As shown, the NC-MSR BS comprises of two or more frequency sub-blocks containing contiguous carriers/RATs separated by empty slots in frequency domain. Each sub-block of frequency consists of contiguous set of carriers, which in turn may belong to the same RAT or to a different RAT. A frequency block may also comprise of carriers belonging to different RATs. For example one frequency block may comprise of GSM carriers and UTRA carriers. Even a sub-block may comprise of contiguous carriers belonging to different RATs. Another operator may operate in empty slot(s). Therefore, emissions in the empty slots need to be maintained below the limit as required by regulatory radio requirements. In NC-MSR, all the carriers/RATs within the overall block of frequency (i.e. the non-contiguous block) share the common radio parts. Hence the generic radio requirements are being defined for all carriers/RATs within the non-contiguous frequency block of NC-MSR.
It should be noted that single RAT BS (e.g. supporting only UTRA FDD or only E-UTRA FDD) may also comprise of non-contiguous carriers. In principle this is a special case of NC-MSR BS, which can also support single RAT scenario in addition to the multi-RAT scenario. The technology described may thus be applied to all these different types of BS which contain non-contiguous carriers or non-contiguous frequency sub-blocks.
Examples of radio nodes other than a BS which may be based on MSR principles are: relay node (which may have different power classes e.g. indoor, pico, thruwall etc), micro, pico and home base-stations, wireless terminal (e.g. user equipment), customer premises equipment (CPE), fixed wireless access (FWA) nodes, repeaters (e.g. Layer-1 and Layer-2 repeaters), wireless devices to assistant location services by receiving signals from and transmitting signals towards target devices (whose location is determined) etc. This means that for instance an MSR relay node may be configured to support any combination of RATs (i.e. can be multi-RATs and/or multi-carrier) e.g. UTRA FDD and E-UTRA FDD. The MSR relay node may also be contiguous or NC-MSR BS.
Furthermore the MSR relay node may be an in-band relay node or an out-band relay node. For an in-band relay node, the backhaul link and the access link operate using the same carrier frequency. For an out-band relay node, the backhaul link and the access link operate using different carrier frequencies. The carrier frequencies may belong to the same or different frequency bands.
The MSR relay node may also be mobile relay (e.g. deployed in a movable vehicle to mainly serve users inside the vehicle and also outside) or a fixed relay node. A wireless terminal may also serve as relay node. A MSR relay node may also support carrier aggregation (CA) or multi-carrier e.g. intra-RAT CA or multi-RAT CA. The MSR relay node may operate in a single hop relay system or in a multi-hop relay system.
The prior art solutions are not sufficient in case of handling MSR BS information, especially in case of non-contiguous MSR BS since a new concept called frequency block has been introduced for the non-contiguous MSR BS. An MSR BS may also comprise a single RAT i.e. all carriers belong to the same RAT. In fact single RAT MSR is a special case of MSR BS. Hence a similar concept (i.e. non-contiguous MSR BS) may also be introduced for single RAT non-contiguous UTRA or E-UTRA base station. Thus, there is no clear indication in prior art solutions how to handle network configuration for all different MSR BS implementations.